By Mike Rowbottom

Dwain Chambers_14_MayMay 13 - Dwain Chambers, in his first 100 metres race since being cleared to compete for Team GB at this summer's Olympic Games, finished a disappointing sixth at the Ponce Grand Prix in Puerto Rico.

The 34-year-old (pictured top), who has been training in Jamaica with elite sprinters including former world record holder Asafa Powell, produced a subdued performance of 10.52sec in a race won by Trinidad and Tobago's Keston Bledman in 10.12.

Bledman claimed victory ahead of Jamaica's Nickel Ashmeade, who clocked 10.15 with Trell Kimmons of the United States third in 10.18 and Chambers' fellow Briton, Simeon Williamson, who has also been training in Jamaica, fourth in 10.42.

Chambers was cleared last month by the Court of Arbitration for Sport (CAS), which overruled a British Olympic Association (BOA) regulation rendering serious doping offenders from competing for Britain at any future Games.

The Londoner is now scheduled to compete over 150 metres against Walter Dix of the United States, the world 100 and 200m silver medallist, at the Powerade Great CityGames Manchester next Sunday (May 20).

Tiffany Porter_14_May
Elsewhere, there was British success for US-born Tiffany Porter (pictured above), who won the 100m hurdles in 12.79 ahead of American pair Kristi Castlin and Tiki James, who recorded 12.91 and 13.21, respectively.

Javier Culson, the world 400m hurdles silver medallist, gave the home fans something to cheer with victory in a world's best time for the year of 48.00.

Reigning world and Olympic 110m hurdles champions Jason Richardson of the US and Cuba's Dayron Robles suffered shock defeats at the hands of Ryan Wilson, the former's compatriot.

The pair were pushed into second and third positions behind Wilson, who clocked 13.43, a time actually matched by Richardson with Robles third in 13.47.

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